Volume 75, Issue 6
  • ISSN: 0002-9637
  • E-ISSN: 1476-1645


As part of an extensive study of the eco-epidemiology of urinary schistosomiasis along the southern coast of Kenya, spatial and temporal transmission patterns were associated with various ponds infested with snails. The household-level spatial pattern of infection for children of various age groups in 2000 was contrasted with historical data from 1984. Significant local clustering of high and low infection levels among school age children was detected, and the spatial extent of clusters and their direction from specific water sources were measured. High infection levels were clustered around ponds known to contain snails that shed cercariae, and low infection levels were concentrated near a river where intermediate host snails were rarely found. The spatial patterns of infection varied between 2000 and 1984 and between age groups. High levels of infection were clustered around different transmission foci in the two study periods, and, for younger children in 2000, were clustered nearer to the transmission foci than for the older children. Simultaneous consideration of the effects of different foci on transmission will allow for targeted application of control measures aimed at interrupting transmission at a local level.


Article metrics loading...

The graphs shown below represent data from March 2017
Loading full text...

Full text loading...



  1. World Health Organization, 2002. Prevention and control of schistosomiasis and soil-transmitted helminthiasis. World Health Organ Tech Rep Ser 912 : 1–57. [Google Scholar]
  2. van der Werf MJ, de Vlas SJ, Brooker S, Looman CW, Nagelkerke NJ, Habbema JD, Engels D, 2003. Quantification of clinical morbidity associated with schistosome infection in sub-Saharan Africa. Acta Trop 86 : 125–139. [Google Scholar]
  3. Jordon P, Webbe G, Sturrock R, 1993. Human Schistosomiasis. Oxon, United Kingdom: CAB International.
  4. Sturrock RF, Kinyanjui H, Thiongo FW, Tosha S, Ouma JH, King CH, Koech D, Siongok TK, Mahmoud AA, 1990. Chemotherapy-based control of schistosomiasis haematobia. 3. Snail studies monitoring the effect of chemotherapy on transmission in the Msambweni area, Kenya. Trans R Soc Trop Med Hyg 84 : 257–261. [Google Scholar]
  5. King CH, Muchiri EM, Ouma JH, 2000. Evidence against rapid emergence of praziquantel resistance in Schistosoma haematobium, Kenya. Emerg Infect Dis 6 : 585–594. [Google Scholar]
  6. Bayne CJ, Loker ES, 1987. Survival within the snail host. Rollinson D, Simpson AJG, eds. The Biology of Schistosomes from Genes to Latrines. London: Academic Press, 347–378.
  7. el Kholy H, Arap Siongok TK, Koech D, Sturrock RF, Houser H, King CH, Mahmoud AA, 1989. Effects of borehole wells on water utilization in Schistosoma haematobium endemic communities in Coast Province, Kenya. Am J Trop Med Hyg 41 : 212–219. [Google Scholar]
  8. Chandiwana SK, Woolhouse ME, 1991. Heterogeneities in water contact patterns and the epidemiology of Schistosoma haematobium. Parasitology 103 : 363–370. [Google Scholar]
  9. Kloos H, Fulford AJC, Butterworth AE, Sturrock RF, Ouma JH, Kariuki HC, Thiongo FW, Dalton PR, Klumpp RK, 1997. Spatial patterns of human water contact and Schistosoma mansoni transmission and infection in four rural areas in Machakos District, Kenya. Soc Sci Med 44 : 949–968. [Google Scholar]
  10. Kloos H, Gazzinelli A, Van Zuyle P, 1998. Microgeographical patterns of schistosomiasis and water contact behavior: examples from Africa and Brazil. Mem Inst Oswaldo Cruz 93 : 37–50. [Google Scholar]
  11. Gazzinelli A, Bethony J, Fraga LA, LoVerde PT, Correa-Oliveira R, Kloos H, 2001. Exposure to Schistosoma mansoni infection in a rural area of Brazil. I: Water contact. Trop Med Int Health 6 : 126–135. [Google Scholar]
  12. Clennon JA, King CH, Muchiri EM, Kariuki HC, Ouma JH, Mungai P, Kitron U, 2004. Spatial patterns of urinary schistosomiasis infection in a highly endemic area of coastal Kenya. Am J Trop Med Hyg 70 : 443–448. [Google Scholar]
  13. Mzugu JM, Tole MP, Ucakuwun EK, 1998. The impact of geology and pit latrines on ground water quality in Kwale District. Hoorweg J, ed. Coastal Ecology Series 4: Dunes, Groundwater, Mangroves and Birdlife in Coastal Kenya. Edloret, Kenya: Moi University, 85–96.
  14. Mzuga JM, Tole MP, Ucakuwun EK, 2001. Contamination of groundwater resources by pit latrines in Kwale District, Kenya. Discovery Innovation 13 (3/4) 203–212. [Google Scholar]
  15. Ochiewo J, 2001. Socio-economic aspects of water management along the coast of Kenya. Hydrobiologia 458 : 267–273. [Google Scholar]
  16. Kariuki HC, Clennon JA, Brady MS, Kitron U, Sturrock RF, Ouma JH, Ndzovu STM, Mungai P, Hoffman O, Hamburger J, Pellegrini C, Muchiri EM, King CH, 2004. Distribution patterns and cercarial shedding of Bulinus nasutus and other snails in the Msambweni area, coast province, Kenya. Am J Trop Med Hyg 70 : 449–456. [Google Scholar]
  17. Peters PA, Warren KS, Mahmoud AA, 1976. Rapid, accurate quantification of schistosome eggs via Nuclepore filters. J Parasitol 62 : 154–155. [Google Scholar]
  18. Kitron UD, Higashi GI, 1985. Schistosoma haematobium in Upper Egypt: analysis of dispersion patterns. Am J Trop Med Hyg 34 : 331–340. [Google Scholar]
  19. King CH, Lombardi G, Lombardi C, Greenblatt R, Hodder S, Kinyanjui H, Ouma J, Odiambo O, Bryan PJ, Muruka J, 1988. Chemotherapy-based control of schistosomiasis haematobia. I. Metrifonate versus praziquantel in control of intensity and prevalence of infection. Am J Trop Med Hyg 39 : 295–305. [Google Scholar]
  20. Ripley BD, 1976. The second-order analysis of stationary point processes. J Appl Prob 13 : 255–266. [Google Scholar]
  21. Getis A, 1984. Interaction modeling using second-order analysis. Environ Plan A 16 : 173–183. [Google Scholar]
  22. Getis A, Ord JK, 1992. The analysis of spatial association by use of distance statistics. Geogr Anal 24 : 189–206. [Google Scholar]
  23. Getis A, Ord JK, 1995. Local spatial autocorrelation statistics: distributional issues and an application. Geogr Anal 27 : 286–306. [Google Scholar]
  24. Ord JK, Getis A, 1996. Local spatial statistics: an overview. Longley P, Batty M, eds. Spatial Analysis: Modeling in a GIS Environment. Cambridge, United Kingdom: Geoinformation International, 261–277.
  25. Getis A, Morrison AC, Gray K, Scott TW, 2003. Characteristics of the spatial pattern of the dengue vector, Aedes aegypti, in Iquitos, Peru. Am J Trop Med Hyg 69 : 494–505. [Google Scholar]
  26. Cecere MC, Vazquez-Prokopec GM, Gurtler RE, Kitron U, 2004. Spatiotemporal analysis of reinfestation by Triatoma infestans (Hemiptera: Reduviidae) following insecticide spraying in a rural community in northwestern Argentina. Am J Trop Med Hyg 71 : 803–810. [Google Scholar]
  27. Vazquez-Prokopec GM, Cecere MC, Canale DM, Gurtler RE, Kitron U, 2005. Spatiotemporal patterns of reinfestation by Triatoma guasayana (Hemiptera: Reduviidae) in a rural community of northwestern Argentina. J Med Entomol 42 : 571–581. [Google Scholar]
  28. Anselin L, 1995. Local indicators of spatial association—LISA. Geogr Anal 27 : 93–115. [Google Scholar]

Data & Media loading...

  • Received : 08 Feb 2006
  • Accepted : 21 Aug 2006

Most Cited This Month

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error